TY - JOUR
T1 - Maturational differences in the isolated isovolumic rabbit heart
AU - Parrish, M. D.
AU - Ayres, N. A.
AU - Kendrick, B. T.
AU - Fixler, David E
PY - 1986
Y1 - 1986
N2 - To determine maturational differences in myocardial pressure work, oxygen consumption, and stability, we evaluated an isolated retrogradely perfused isovolumic rabbit heart model in newborns (0-6 days of age, mean 3.3 ± 1.9 days), immatures (4-6 wk) and adults (5-7 mo). To reduce ischemic time and cardiac trauma, the hearts were isolated and instrumented within the chest cavity. By design, there were no significant age-related differences in coronary flow per gram, heart rate, or resting pressure. Left ventricular developed pressure was similar at all ages, but myocardial oxygen consumption was much lower in newborns and immatures than in adults. Coronary resistance was lower in the younger hearts. There were no significant age-related differences in contractility, left ventricular stiffness, or myocardial pH. All hearts were stable for 120 min, but thereafter immatures and adults deteriorated more rapidly than newborns. The study demonstrates that this model is technically suitable for the study of age-related differences in cardiac physiology. Furthermore, newborn and immature hearts are able to more efficiency use oxygen to develop left ventricular pressures, possible due to a lower wall tension.
AB - To determine maturational differences in myocardial pressure work, oxygen consumption, and stability, we evaluated an isolated retrogradely perfused isovolumic rabbit heart model in newborns (0-6 days of age, mean 3.3 ± 1.9 days), immatures (4-6 wk) and adults (5-7 mo). To reduce ischemic time and cardiac trauma, the hearts were isolated and instrumented within the chest cavity. By design, there were no significant age-related differences in coronary flow per gram, heart rate, or resting pressure. Left ventricular developed pressure was similar at all ages, but myocardial oxygen consumption was much lower in newborns and immatures than in adults. Coronary resistance was lower in the younger hearts. There were no significant age-related differences in contractility, left ventricular stiffness, or myocardial pH. All hearts were stable for 120 min, but thereafter immatures and adults deteriorated more rapidly than newborns. The study demonstrates that this model is technically suitable for the study of age-related differences in cardiac physiology. Furthermore, newborn and immature hearts are able to more efficiency use oxygen to develop left ventricular pressures, possible due to a lower wall tension.
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U2 - 10.1152/ajpheart.1986.251.6.h1143
DO - 10.1152/ajpheart.1986.251.6.h1143
M3 - Article
C2 - 3789167
AN - SCOPUS:0023013813
SN - 0363-6135
VL - 251
SP - H1143-H1148
JO - American Journal of Physiology - Heart and Circulatory Physiology
JF - American Journal of Physiology - Heart and Circulatory Physiology
IS - 6 (20/6)
ER -